Fix bug #9104 - winbindd can mis-identify idle clients - can cause crashes and NDR...
[samba.git] / libcli / nbt / lmhosts.c
1 /*
2    Unix SMB/CIFS implementation.
3
4    manipulate nbt name structures
5
6    Copyright (C) Andrew Tridgell 1994-1998
7    Copyright (C) Jeremy Allison 2007
8    Copyright (C) Andrew Bartlett 2009.
9
10    This program is free software; you can redistribute it and/or modify
11    it under the terms of the GNU General Public License as published by
12    the Free Software Foundation; either version 3 of the License, or
13    (at your option) any later version.
14
15    This program is distributed in the hope that it will be useful,
16    but WITHOUT ANY WARRANTY; without even the implied warranty of
17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18    GNU General Public License for more details.
19
20    You should have received a copy of the GNU General Public License
21    along with this program.  If not, see <http://www.gnu.org/licenses/>.
22 */
23
24 #include "includes.h"
25 #include "lib/util/xfile.h"
26 #include "lib/util/util_net.h"
27 #include "system/filesys.h"
28 #include "system/network.h"
29
30 /********************************************************
31  Start parsing the lmhosts file.
32 *********************************************************/
33
34 XFILE *startlmhosts(const char *fname)
35 {
36         XFILE *fp = x_fopen(fname,O_RDONLY, 0);
37         if (!fp) {
38                 DEBUG(4,("startlmhosts: Can't open lmhosts file %s. "
39                         "Error was %s\n",
40                         fname, strerror(errno)));
41                 return NULL;
42         }
43         return fp;
44 }
45
46 /********************************************************
47  Parse the next line in the lmhosts file.
48 *********************************************************/
49
50 bool getlmhostsent(TALLOC_CTX *ctx, XFILE *fp, char **pp_name, int *name_type,
51                 struct sockaddr_storage *pss)
52 {
53         char line[1024];
54
55         *pp_name = NULL;
56
57         while(!x_feof(fp) && !x_ferror(fp)) {
58                 char *ip = NULL;
59                 char *flags = NULL;
60                 char *extra = NULL;
61                 char *name = NULL;
62                 const char *ptr;
63                 char *ptr1 = NULL;
64                 int count = 0;
65
66                 *name_type = -1;
67
68                 if (!fgets_slash(line,sizeof(line),fp)) {
69                         continue;
70                 }
71
72                 if (*line == '#') {
73                         continue;
74                 }
75
76                 ptr = line;
77
78                 if (next_token_talloc(ctx, &ptr, &ip, NULL))
79                         ++count;
80                 if (next_token_talloc(ctx, &ptr, &name, NULL))
81                         ++count;
82                 if (next_token_talloc(ctx, &ptr, &flags, NULL))
83                         ++count;
84                 if (next_token_talloc(ctx, &ptr, &extra, NULL))
85                         ++count;
86
87                 if (count <= 0)
88                         continue;
89
90                 if (count > 0 && count < 2) {
91                         DEBUG(0,("getlmhostsent: Ill formed hosts line [%s]\n",
92                                                 line));
93                         continue;
94                 }
95
96                 if (count >= 4) {
97                         DEBUG(0,("getlmhostsent: too many columns "
98                                 "in lmhosts file (obsolete syntax)\n"));
99                         continue;
100                 }
101
102                 if (!flags) {
103                         flags = talloc_strdup(ctx, "");
104                         if (!flags) {
105                                 continue;
106                         }
107                 }
108
109                 DEBUG(4, ("getlmhostsent: lmhost entry: %s %s %s\n",
110                                         ip, name, flags));
111
112                 if (strchr_m(flags,'G') || strchr_m(flags,'S')) {
113                         DEBUG(0,("getlmhostsent: group flag "
114                                 "in lmhosts ignored (obsolete)\n"));
115                         continue;
116                 }
117
118                 if (!interpret_string_addr(pss, ip, AI_NUMERICHOST)) {
119                         DEBUG(0,("getlmhostsent: invalid address "
120                                 "%s.\n", ip));
121                 }
122
123                 /* Extra feature. If the name ends in '#XX',
124                  * where XX is a hex number, then only add that name type. */
125                 if((ptr1 = strchr_m(name, '#')) != NULL) {
126                         char *endptr;
127                         ptr1++;
128
129                         *name_type = (int)strtol(ptr1, &endptr, 16);
130                         if(!*ptr1 || (endptr == ptr1)) {
131                                 DEBUG(0,("getlmhostsent: invalid name "
132                                         "%s containing '#'.\n", name));
133                                 continue;
134                         }
135
136                         *(--ptr1) = '\0'; /* Truncate at the '#' */
137                 }
138
139                 *pp_name = talloc_strdup(ctx, name);
140                 if (!*pp_name) {
141                         return false;
142                 }
143                 return true;
144         }
145
146         return false;
147 }
148
149 /********************************************************
150  Finish parsing the lmhosts file.
151 *********************************************************/
152
153 void endlmhosts(XFILE *fp)
154 {
155         x_fclose(fp);
156 }
157